Disclaimer, i love little A so much. This is just a theory.
What if the uncle left the farm to protect the farm from his nephew? Since little A is "experiment" too (based on what other psychopath pig thaf stabbed suit guy) because he was showing behaviors of a psychopath when he was young. Now that Uncle (Big A) knows little A is there, he immediately went back because he knows something could trigger little A and could go in Kill mode again.
Disclaimer, i love little A so much. This is just a theory.
What if the uncle left the farm to protect the farm from his nephew? Since little A is "experiment" too (based on what other psychopath pig thaf stabbed suit guy) because he was showing behaviors of a psychopath when he was young. Now that Uncle (Big A) knows little A is there, he immediately went back because he knows something could trigger little A and could go in Kill mode again.